Refining of south texas lubricating oil



Patented ab. 1, 1936 2,029,605

UNITED STATES PATENT OFFICE REFINING OF SOUTH TEXAS LUBRIGATING OIL Wilson Hull Beardsley, Houston, Tex., assignor to Sinclair Refining Company, New York, N. Y., a corporation of Maine No Drawing. Application March 9, 1932, Serial No. 597,810

1 Claim. (Cl. 19640) My invention relates to improvements in the number exceeding 0.2 are avoided if sufficient manufacture of lubricating oils. More particuwater is used to assist the separation of the sludge larly, my invention relates to improvements in formed. The amounts of water used in accordthe treatment with sulphuric acid of lubricating ance with my invention are substantially larger 5 oil stocks derived from South Texas type crudes. than those hitherto used. I find the use of water One conventional treatment to which lubricatin amounts approximating 1.5-3.0 per cent by ing oil stocks are commonly subjected comprises volume on the oil particularly advantageous in agitation of the oil with sulphuric acid followed the treatment of stocks of this type. I have been by separation of the sludge formed assisted by able successfully and regularly thus to treat stocks the addition of water. This treatment requires derived from South Texas crudes having acid 10 skilful manipulation in every case, but no unnumbers as high as 0.5-0.7 and higher without imusual difiiculties are encountered where the oil pairing the quality or". the stock treated in any has a sufliciently low acid number. Lubricating respect. At the same time I have been able to stocks derived from South Texas crudes, howdevelop marked economies, for example, in the ever, frequently have a high acid number and, amount of caustic soda required in preliminary 15 as applied to such oils, the treatment has involved treatment. My invention may be carried out just both difficulties and prejudices. The use or" too as the conventional treatment is carried out exmuch Water, to induce the sludge separation, or cent in that a substantially larger amount of acid break, tends to decompose the sludge and water is used to assist the separation of sludge to introduce or reintroduce objectionable constituformed and in that it is applicable to stocks hav- 20 ents into the oil. In the treatment of. oils having ing acid numbers exceeding 0.2 or thereabouts.

a high acid number, the addition of water tends In one aspect my invention comprises, in comto involve emulsification, and the addition of bination, a preliminary neutralization treatment water has in such cases been further limited for insufficient to reduce the acid number of the this reason. In general the art has regarded stock to 0.2 or less, distillation with 1-2 pounds of 25 it necessary to reduce the acid number to some caustic soda per barrel of oil as compared to 6-8 value not exceeding about 0.2 by some preliminary pounds per barrel for example, and a sulphuric treatment such as chstillation with caustic soda, acid treatment in which the amount of water in the treatment of South Texas type stocks havused to assist the separation of the sludge formed mg a higher acid number, and to limit the addiapproximates 1.5-3.0 per cent by volume on the 30 tion of water not to exceed a fraction of one per oil. My invention may be practiced in any concent by volume on the oil. ventional apparatus.

In referring to lubricating oils and lubricat- I claim: ing stocks, I refer to oils and oil stocks having In the refining of South Texas lubricating oil viscosities upwards of 100 at 100 F. (Saybolt stocks having an acid number substantially ex- 35 Universal). In referring to acid number, I receeding 0.2 with sulphuric acid, the improvement fer to the number of milligrams of. potassium which comprises subjecting the oil to a prelimihydroxide required to neutralize one gram of the nary neutralization treatment insufiicient to reoil using phenolphthalein as the indicator (A, S. duce the acid number of the oil to 0.2, thereafter T. M. Tentative Standard D 188--27T 1925- subjeoting the oil to treatment with sulphuric 40 1931). acid and adding an amount of water approxi- I have discovered that the difficulties involved mating 1.5-3.0% by volume on the oil to assist and believed to be involved in the treatment with the separation of the sludge formed. sulphuric acid of lubricating oil stocks derived from South Texas crudes and having an acid WILSON HULL BEARDSLEY. 45 

